Battle of Cambrai

In November 1917, a plan had been proposed that tanks in mass, in co-operation with all arms, should break through the Hindenburg Line in the area of a town called Cambrai in Northern France. The plan was that the German line would be broken by a concentrated attack across a narrow front (around 5 miles) between the Canal du Nord and St Quentin canal and then Cambrai would be encircled and Bourlon Ridge captured.

Certain newly developed tactics would be employed, including the use of air interdiction and mixed infantry and tank formations. Cavalry was also included in the plan, expanding through a 'cavalry gap' towards the River Sensée. The assault was assigned to the divisions of the British 4th Army; of these no fewer than 10 were still recovering from the slaughter at Third Ypres. The defending force was part of the German Army under General Georg von der Marwitz, designated Gruppe Caudry (or XIII Corps) it initially consisted of the 20th, 54th, 9th Reserve and 183rd divisions.

The Tank Corps under Major General Hugh Elles provided its entire strength, over 350 fighting Mark IV tanks for the first day, 476 in all over the course of the battle. There were 216 in the initial advance with 96 in reserve. Some of the tanks were equipped with massive wood fascines to aid trench crossing or special 'grapnels' to aid wire removal.

Great care was taken to preserve the secrecy and surprise of the attack. Tanks, guns, horses and men assembled at night and were hidden in nearby woods and villages. All manner of deceptions was employed so that, although the Germans had hints of the coming storm, they never confirmed it and subsequently took no extra precautions.

At 0620 hrs on the 20th November, the attack opened with a carefully prepared and predicted but unregistered fire barrage by 1,003 guns on key German defences followed by smoke and a creeping barrage at 300 yards ahead to cover the first advances. The tanks (9 Battalions) rolled forward against a 6 mile stretch of front near Cambrai, leading 6 Infantry and 5 Cavalry Divisions to an assault on the Hindenburg Line.

They crossed the deep, wide trenches of the line before dawn using fascines (large bundles of brushwood carried by tanks to be dropped into ravines, etc). From left to right the Battle line swept forward. Except at the key village of Flesquirers, guarding the way to Bourlon Wood, the timetable was maintained and the new tactics worked.

By nightfall, an advance of up to 5 miles had been made, 8000 prisoners and 100 guns had been taken and a great gap ripped in the German defences through which an exploiting force might have passed deep into the enemy's rear area.

In the centre the 51st (Highland) Division was stalled at its first objective, Flesquières, and left the advances around it exposed. It is believed that the GOC of the 51st Div substituted his own tank drill for the standard one and that an excessive space between the tanks and the infantry contributed to the failure. Flesquières was also one of the strongest points in the German line and was flanked by other strong points. Its defenders also acquitted themselves well against the tanks, engaging them aggressively. Almost 40 tanks were knocked out by the Flesquières artillery, including sixteen by a single gun manned by a lone gunner. Despite this, the Germans were forced to abandon Flesquières during the night.

On the left, the 62nd (2nd West Riding) Division swept all the way through Havrincourtand Graincourt to within reach of the woods on Bourlon Ridge and the 36th (Ulster) Division on their left reached the Bapaume-Cambrai road. Of the tanks, 180 were out of action after the first day, although only 65 had been destroyed. Of the remainder, 71 had suffered mechanical failure and 43 had been 'ditched'. The British had suffered around 4,000 casualties and had taken 4,200 prisoners, a casualty rate half that of Passchendale, and a greater advance in 6 hours than in 3 months there.

However, the British had failed to reach the heights of Bourlon Ridge. The German command was quick to send up reinforcements overnight and was relieved that the British did not manage to fully exploit their early gains. When the battle was renewed on the 21st November the pace of the British advance was greatly slowed. The abandoned Flesquières and then Cantaing were captured in the very early morning but in general, the British took to reinforcing their gains rather than expanding. The efforts of III Corps were officially halted and attention was turned to IV Corps.

The continuing effort was aimed at Bourlon Ridge. Fighting was fierce around Bourlon and at Anneux, just before the woods, it was very costly. German counter attacks squeezed the British out of Moeuvres (21st) and Fontaine (22nd). Even when Anneux was taken the 62nd found themselves unable to enter Bourlon Woods.

The British were left exposed in a salient. Haig still wanted Bourlon Ridge and the exhausted 62nd Division was replaced by the 40th Division on the 23rd November. Supported by almost a 100 tanks and 430 guns, the 40th attacked into the woods of Bourlon Ridge but making little progress. The Germans had put 2 Divisions of Gruppe Arras on the ridge with another 2 in reserve, Gruppe Caudry was reinforced and to challenge the RFC, the Squadrons under the Red Baron were assigned. The British 40th did reach the crest of the ridge but were held there and suffered over 4,000 casualties for their efforts in 3 days.

More British troops were pushed in to move beyond the woods to Fointaine, but the British reserves were rapidly depleted and the Germans were still sending in more reinforcements. The final British effort was on the 27th November by the 62nd Division aided by 30 tanks. Early success was soon reversed by a German counter attack. The British now held a salient roughly 11 km by 9.5 km with its front along the crest of the ridge. On the 28th November the offensive was officially ended and the British troops were ordered to lay wire and dig in. The Germans were quick to concentrate their artillery on the new British positions. On the 28th November over 16,000 rounds were fired into the wood.

As the British used up their strength to take the ridge, the Germans were reinforcing the area more generally. As early as the 23rd November, the German High Command felt that a British breakthrough would not occur and began to consider a counter offensive. 20 Divisions were arrayed in the Cambrai area. The Germans intended to retake the Bourlon salient and also to attack around Havrincourt while diversionary attacks would hold IV Corps.

The German attack began at 0700 on the 30th November. Almost immediately the majority of III Corps Divisions were heavily engaged. Gruppe Caudry attacked from Bantouzelle to Rumilly and aimed for Marcoing. Gruppe Busogny was targeted from Banteux. The initial speed of the German infantry advance was completely unexpected by the British.

In the south, the German advance spread across 8 miles and came within a few miles of the vital village of Metz and its link to Bourlon. At Bourlon itself, they met with stiffer resistance. The British had assigned 8 Divisions worth of fire support to the ridge and the Germans suffered heavy casualties. Despite this the Germans closed and there was fierce fighting. British units displayed reckless determination - one group of 8 British machine guns fired over 70,000 rounds in efforts to stem the German advance around Bourlon.

The concentration of British effort to hold the ridge was impressive but it allowed the German advance elsewhere greater opportunities. Only the fortunate arrival of British tanks and the fall of night allowed some form of line to be held. By the following day the impetus of the German advance was lost, but continued pressure on the 3rd December led to the German capture of La Vacquerie and the withdrawal of the British from the east of the St Quentin canal. The Germans had reached a line looping from the ridge at Quentin to near Marcoing. Their capture of Bonvais ridge made the British hold on Bourlon precarious.

On the 3rd December Haig ordered a retreat from the salient and by the 7th December all the British gains were abandoned except for a portion of the Hindenburg line around Havrincourt, Ribécourt and Flesquières. The German had exchanged this territorial loss for a sweep of land to the south of Welsh ridge.

Total casualties for both sides were around 45,000 each with 11,000 Germans and 9,000 British taken prisoner. In terms of territory, the Germans had recovered the early losses and a little more. Despite the outcome, the battle was seen as evidence than even the strongest trench defences could be overcome by a massive tank attack. By the end of the battle on the 5th December, the Tank Corps was exhausted and although nothing as remarkable as the first day's result was achieved again, the Battle of Cambrai changed the tactical climate of the war and of warfare.